1. Field of Invention
Various exemplary embodiments of the present invention relate generally to an electronic device, and more particularly, to a semiconductor memory device, a method of operating the same and a memory system including the same.
2. Description of Related Art
A semiconductor memory device is a storage device that is realized using a semiconductor made from, for example, silicon (Si), germanium (Ge), gallium arsenide (GaAs) or indium phosphide (InP). Semiconductor memory devices may be classified into volatile memory devices and non-volatile memory devices.
Volatile memory devices are unable to retain the stored data when the power is off. Examples of the volatile memory devices may include Static Random Access Memory (SRAM), Dynamic RAM (DRAM) and Synchronous DRAM (SDRAM). Non-volatile memory devices can retain the stored data regardless of power on/off conditions. Examples of the non-volatile memory include Read Only Memory (ROM), Mask ROM (MROM), Programmable ROM (PROM), Erasable Programmable ROM (EPROM), Electrically Erasable and Programmable ROM (EEPROM), flash memory, Phase-change RAM (PRAM), Magnetic RAM (MRAM), Resistive RAM (RRAM) and Ferroelectric RAM (FRAM). Flash memories may be classified into NOR-type memories and NAND-type memories.
A semiconductor memory device operates by receiving an external power supply voltage to operate. When the external power supply voltage being supplied is suddenly interrupted, the semiconductor memory device stops operating. For example, when the supply of the external power supply voltage is cut off during a program operation, the semiconductor memory device may not complete the program operation properly.